package Java.j1;

import java.util.Scanner;

public class AcWing_612 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int R = sc.nextInt();
        System.out.printf("VOLUME = %.3f\n", (4.0/3.0) * 3.14159 * Math.pow(R, 3));
    }
}
